@m1:0;
*{
    margin: @m1;
    padding: @m1;
}
ul{
    width: 300px;
    margin: 100px auto;
    list-style: none;
    li{
        height: 30px;
        line-height: 30px;
        padding-left: 20px;
        &:nth-child(2n+1){
            background: yellow;
        }
        &:nth-child(2n){
            background: skyblue;
        }
        &:hover{
            background:hotpink;
            color:white;
            font-weight: bold;
        }
    }
}


